Various styli are known and typically serve in conjunction with a scribing surface that is configured to work with a corresponding stylus. Generally speaking, a stylus is typically a hand-held writing utensil that often (but not exclusively) has a pencil-like elongated form factor and that includes at least one pointed end configured to interact with the scribing surface. Using a stylus as an input mechanism with, for example, a display, offers a variety of advantages over a fingertip including the opportunity for increased precision as well as an expression modality that accords with the user's own past experience with a pencil or pen.
Some styli include an integral force sensor. So configured, the stylus can detect the force that the user employs from moment to moment when bearing the stylus tip down on a scribing surface. This information can be used by a corresponding host electronic device in a variety of ways. As one simple example, the amount of force being applied to the scribing surface via stylus input can serve to control the relative thickness of a corresponding line being rendered on a display.
Such styli typically employ a movable nib as the stylus tip. This movable nib, in turn, mechanically couples to the force sensor. In this manner, as the nib is forced to move into the stylus as the user applies pressure, the force sensor detects this increased pressure and the sensed change is processed to provide an application-specific stylus input to the host device. Ordinary approaches in these regards use force sensors that employ optical, piezoelectric, and/or resistive sensors. Although these expedients can provide useful and reliable sensed-force information, typical known arrangements have drawbacks.